Just one more thing to add to this discussion. Dave, close your eyes for a bit, because this is going to involve neuromuscular efficiency.
This discussion isn't about how to build strength -- the answer to that is squats, dls, press, bp, chins, etc. It's about rate of force development: the ability to apply that strength quickly, explosively and well coordinated.
It seems to me (and I'll admit that I'm speaking from the position of a person who is a beginner at Olympic lifting, has only played around with sandbag training, and has no experience in football), that it is harder to train RFD with an awkward load than with a well balanced barbell placed in the position of maximal biomechanical efficiency. Kegs, sandbags, logs, etc., may well have a part in training how to apply that RFD to hard to control objects in a coordinated way, but few things are going to beat the olympic lifts in training the body how to explode quickly.
That being said, if power cleans and snatches from the hang are all that can be effectively learned, that would probably suffice for RFD.